This proposal is a grant request to the Biomedical Research Support (BRS) grant program of the Division of Research Resources (DRR) to establish a multi-user facility for automated synthesis, purification and low temperature storage of polypeptides. The Graduate School of Biomedical Sciences of the University of Texas Medical Branch (UTMB) at Galveston receives support from BRS, grant # DHHS 2S07 RR 07205-05 and is thus eligible to apply for a BRS-DRR grant. Funding is requested for a peptide synthesizer, a high performance liquid chromatography (HPLC) system and a low temperature freezer to provide a peptide synthesis capability for 14 documented ongoing biomedical research projects, most of which are currently funded by the National Institutes of Health (NIH). These programs include six projects dealing with molecular basis of ligand-receptor interactions, three projects dealing with immunological dissection of protein structure and function, three projects involving neurochemistry and the nature of specific peptides as neurotransmitter molecules, one project involving membrane protection from free radicals, and one project involving the use of peptides as ion channel modifiers in artificial membranes. Acquisition of the proposed peptide synthesizer is required to more effectively meet the stated objectives of these NIH approved projects and allow these investigators to expand their research efforts to keep pace with the rapid progress made possible by the use of synthetic peptides. The peptide synthesizer will be housed adjacent to, and will be operated in conjunction with, a centralized Protein Chemistry Laboratory. The Protein Chemistry Laboratory has an established record of ongoing shared instrumentation usage and has an administrative mechanism in place for dealing with shared costs. A Research Advisory Committee responsible to the Dean of the Graduate School will assist the Program Director in administrative and scientific review of the peptide synthesizer facility to insure proper sharing and maximizing the use of this instrumentation. The UTMB administration has agreed to provide space, a Research Associate salary, and continued support for service to operate this facility allowing users to be charged only for consumable supplies.